wiki useful?

Okay, in a closed environment ie.: library employees, information in a wki could be taken as gospel. As a community site to share information about the area, a wiki would be so much fun and useful. As a place to gather information that might be really important to you or for a paper, I have doubts. As a place to start when you have a subject but have not got a clue as how to go on, a wiki would indeed be useful. After as quick looksee it would be best to go to validated sites and get the "right stuff". I simply do not trust wikis except for fun.